1. Field of the Invention
The present invention relates to an apparatus and method for visualizing the shape formed by assembling sewing patterns, and more particularly to a three-dimensional image display method suitable for the apparatus for visualizing the shape formed by assembling sewing patterns.
2. Description of the Prior Art
Heretofore, computer-aided techniques in the production process in the apparel industry have been used in grading and marking, and gradually been applied to pattern making. In particular, a CAD (Computer Aided Design) system is used in the pattern making as follows:
(a) Original sewing patterns and silhouette patterns are registered in a data base so that a sewing pattern which conforms to a predetermined condition is searched. PA1 (b) The sewing pattern image prepared by the above searching is subjected to various image processing steps. PA1 inputting to a calculation unit three-dimensional coordinate values indicating a shape of a dress form and main dimensions of a shape formed by assembling sewing patterns on the dress form; PA1 generating by the calculation unit three-dimensional coordinate values indicating the shape formed by assembling the sewing patterns according to the inputted three-dimensional coordinate values and the main dimensions; PA1 generating by an image processing unit a two-dimensional projection image from the calculated three-dimensional coordinate values; and PA1 displaying the generated two-dimensional projection image as a two-dimensional projection image of the shape formed by assembling the sewing patterns on a display screen of a display unit. PA1 input means for inputting three-dimensional coordinate values indicating a shape of a dress form and main dimensions of a shape formed by assembling sewing patterns on the dress form; PA1 calculation means for generating three-dimensional coordinate values indicating the shape formed by assembling the sewing patterns according to the inputted three-dimensional coordinate values and the main dimensions; PA1 image processing means for generating a two-dimensional projection image from the calculated three-dimensional coordinate values; and PA1 display means for displaying the generated two-dimensional projection image as a two-dimensional projection image of the shape formed by assembling the sewing patterns on a display screen of the display means. PA1 determining in advance a correlation between a first coordinate position indicating the position of a viewpoint in a three-dimensional space and a second coordinate position indicating the position of the viewpoint in a two-dimensional space, the viewpoint and the first coordinate position being used for generating a three-dimensional display image, and the second coordinate position being used for inputting instruction; PA1 setting the two-dimensional space on the display screen, and displaying the two-dimensional space and the viewpoint on the two-dimensional space in specific figures on the display screen of the display means; PA1 inputting the second coordinate position of the viewpoint from a coordinate input unit; PA1 moving the specific figure indicating the viewpoint to a position, which corresponds to the second coordinate position, on the display screen of the display means each time the second coordinate position of the viewpoint is inputted from the coordinate input unit; and PA1 converting the second coordinate position inputted from the coordinate input unit into the first coordinate position of the viewpoint according to the correlation. PA1 display means for setting a two-dimensional space on a display screen, and displaying the two-dimensional space and a viewpoint on the two-dimensional space in specific figures on a display screen of the display means; PA1 coordinate input means for inputting a second coordinate position indicating a position of the viewpoint on the two-dimensional space; PA1 display controlling means for moving a specific figure indicating the viewpoint to a position, which corresponds to the second coordinate position, on the display screen of the display means each time the second coordinate position of the viewpoint is inputted from the coordinate input unit; and PA1 calculation processing means for determining in advance a correlation between a first coordinate position indicating the position of a viewpoint in a three-dimensional space and the second coordinate position indicating the position of the viewpoint in the two-dimensional space, the viewpoint and the first coordinate position being used for generating a three-dimensional display image, and the second coordinate position being used for inputting instruction, and for converting the second coordinate position inputted from the coordinate input means into the first coordinate position of the viewpoint according to the correlation.
The image processing steps include point creation, point movement, line drawing on the sewing pattern, and rotation and division of the sewing pattern and the like.
Although using such image processing techniques makes it possible to easily perform two-dimensional preparation and modification of sewing patterns, wearing comfortableness, design balance, size adaptability and the like cannot be evaluated until clothes are actually fabricated. Therefore, there have been increasing requirements from users to confirm a shape formed by assembling a plurality of sewing patterns on a CAD display screen.
To present the shape of assembled sewing patterns, there has been proposed a method in which horizontal cross sections of assembled sewing patterns are approximated by using ellipses and straight lines to generate three-dimensional shape data from the two-dimensional shape data of the sewing patterns (The Transactions of the Institute of Electronics and Communications Engineers of Japan, Vol. J69-D, No. 3, pp. 451-459, March, 1986).
Since the proposition teaches the way to represent a three-dimensional shape of assembled sewing patterns, it has become possible to visually display two-dimensional projection images of the assembled shape provided the three-dimensional shape data is obtained.
In general, when a three-dimensional object of the shape specified by such three-dimensional shape data is displayed, a two-dimensional projection image such as a perspective image of the object observed from a certain viewpoint is displayed. For this purpose, a user inputs three-dimensional coordinates in the form of numeral values.
The above proposition, however, approximates the circumferences of the horizontal cross sections of the assembled sewing patterns by four quarter-ellipses and two straight lines. This presents a problem in that a three-dimensional shape represented by the three-dimensional shape data takes somewhat squarish form different from the outer shape of an actual wearer or a dress form, thus presenting shapes different from those formed by actually wearing clothes.
Furthermore, a user is required to determine relative positional relationships between the viewpoint and the object by drawing or the like. The entire shape of the displayed perspective image cannot be perceived if the inputted viewpoint is too high or too low. Therefore, the user must input viewpoint coordinates several times on the trial and error basis, and display the perspective image on the display screen every time in order to obtain a good perspective image.